In conventional analyzers using so-called "dried" test elements, at least some designs provide the patients' serum for analysis in cups mounted on a rotating tray. The tray comes in segments, such as quarter segments of an annular ring, that are mounted and dismounted onto a rotating platform. The analyzer operator removes a tray segment from the platform, mounts serum-containing cups along the outer rim portion of the tray, and then remounts the tray onto the platform.
Conventionally such tray segments are interlocked with the platform at two locations. One location, a post on the platform close to the platform axis, engages a hole in an inner rim of the tray quarter-segment. At a second location, a rib on the outer edge of the platform engages a corresponding slot adjacent the outer rim of the tray segment.
Such a design requires a careful machining of the engaging post-and-hole configurations, and of the engaging rib-and-slot configurations. In addition, they require some attention on the part of the user so that the tray is properly remounted without spilling the contents of the cups. The user also must be cautious to not bend or damage the interacting parts, lest the interlock of pin-and-hole, or rib-and-slot, be prevented or rendered difficult.
It is true that these factors of manufacture and use have been manageable, and many analyzers are successfully being used with such features. However, there has been a need, prior to this invention, to simplify the mounting of the tray on its platform. That is, a better mounting has been sought that would minimize the criticality of parts tolerances, as well as the care required by the user.